1. Field of the Invention
The present invention relates to a mask frame assembly for thin film deposition, and more particularly, to a mask frame assembly for thin film deposition which prevents a mask from deforming.
2. Description of the Related Art
In general, organic light emitting display devices (OLEDs) including a thin film transistor (TFT) may be used in display devices in mobile appliances such as digital cameras, video cameras, portable information terminals, smart phones, tablet computers, or ultra-thin laptop computers, and electronic devices such as ultra-thin televisions.
An OLED emits lights of different colors when holes and electrons injected into an anode and a cathode recombine in an organic emission layer. The OLED is a stack type display device in which the organic emission layer is inserted between the anode and the cathode.
However, according to the above-described structure, highly efficient light emission may not be performed, and thus, intermediate layers such as an electron injection layer, an electron transport layer, a hole transport layer, and a hole injection layer are selectively inserted between the electrodes and the organic emission layer.
The electrodes and the intermediate layers, including the organic emission layer of the OLED, may be formed via a photolithography method or a deposition method.